©1994 Burr-Brown Corporation

PDS-1242B

Printed in U.S.A. May, 1995

Difet®; Burr-Brown Corporation

FEATURES

q LOW INPUT BIAS CURRENT: 3fA typ

q BUFFERED GUARD DRIVE PINS

q LOW OFFSET VOLTAGE: 2mV max

q HIGH COMMON-MODE REJECTION:

84dB (G = 10)

q LOW QUIESCENT CURRENT: 1mA

q INPUT OVER-VOLTAGE PROTECTION:

±40V

APPLICATIONS

q LABORATORY INSTRUMENTATION

q pH MEASUREMENT

q ION–SPECIFIC PROBES

q LEAKAGE CURRENT MEASUREMENT

Ultra Low Input Bias Current

INSTRUMENTATION AMPLIFIER

INA116

INA116

INA116

A

1

A

2

A

3

60k

Ω

60k

Ω

60k

Ω

60k

Ω

V

IN

V

IN

R

G

V+

V–

INA116

V

O

Ref

G = 1 +

50k

Ω

R

G

–

+

25k

Ω

25k

Ω

Guard

Guard

Guard

Guard

+1

+1

Over-Voltage

Protection

Over-Voltage

Protection

2

3

4

1

16

5

6

7

8

11

9

13

®

DESCRIPTION

The INA116 is a complete monolithic FET-input instru-

mentation amplifier with extremely low input bias

current. Difet ® inputs and special guarding techniques

yield input bias currents of 3fA at 25

°C, and only 25fA

at 85

°C. Its 3-op amp topology allows gains to be set

from 1 to 1000 by connecting a single external resistor.

Guard pins adjacent to both input connections can be

used to drive circuit board and input cable guards to

maintain extremely low input bias current.

The INA116 is available in 16-pin plastic DIP and SOL-16

surface-mount packages, specified for the –40

°C to +85°C

temperature range.

International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111

Internet: http://www.burr-brown.com/ • FAXLine: (800) 548-6133 (US/Canada Only) • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132

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